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1.
Small ; : e2405786, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291954

RESUMEN

Multilayer-structured nanocomposites are recognized as a prominent strategy for overcoming the paradox between the breakdown strength (Eb) and polarization (P) to achieve superior energy storage performance. However, current multilayer-structured nanocomposites involving substantial quantities of nanofillers (>10 vol.%) for high dielectric constant as polarization layer will inevitably deteriorate mechanical properties and breakdown strength. Herein, an innovative approach is reported to breaking conventional rules by designing a multilayered polymer composite with ultralow loading of Al2O3 nanoparticles, i.e., 0.3 vol.% for polarization layers and 2 vol.% for insulation layers. By modulating the spatial distribution of Al2O3 nanoparticles in polymer, a significantly increased interfacial dipole response is induced, and deep interfacial traps are constructed to capture the mobile charges, thereby suppressing high-temperature conduction loss. The resulting multilayered polymer composite exhibits an unparalleled discharged energy density of 7.8 J cm-3 with a charging/discharging efficiency exceeding 90% at 150 °C. This work provides valuable insights into achieving superior capacitive performance in multilayer composite films operating under extreme conditions.

2.
Small ; 19(15): e2207135, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36610055

RESUMEN

Electrocatalytic hydrogen evolution is an important approach to produce clean energy, and many electrocatalysts (e.g., platinum) are developed for hydrogen production. However, the electrocatalytic efficiency of commonly used metal catalysts needs to be improved to compensate their high cost. Herein, the electrocatalytic efficiency of platinum nanoparticles (PtNPs) in hydrogen evolution is largely improved via simple surface adsorption of sub-monolayer p-aminothiophenol (PATP) molecules. The overpotential goes down to 86.1 mV, which is 50.2 mV lower than that on naked PtNPs. This catalytic activity is even better than that of 20 wt.% Pt/C, despite the much smaller active surface area of PATP-adsorbed PtNPs than Pt/C. It is theoretically and experimentally confirmed that the improved electrocatalytic activity in hydrogen evolution can be attributed to the change in electronic structure of PtNPs induced by surface adsorption of PATP molecules. More importantly, this strategy can also be used to improve the electrocatalytic activity of palladium, gold, and silver nanoparticles. Therefore, this work provides a simple, convenient, and versatile method for improving the electrocatalytic activity of metal nanocatalysts. This surface adsorption strategy may also be used for improving the efficiency of many other nanocatalysts in many reactions.

3.
Small ; 19(52): e2303933, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37574266

RESUMEN

Exploiting novel strategies for simultaneously harvesting ubiquitous, renewable, and easily accessible solar energy based on the photothermal effect, and efficiently storing the acquired thermal energy plays a vital role in revolutionizing the current fossil fuel-dominating energy structure. Developing black phosphorene-based phase-change composites with optimized photothermal conversion efficiencyand high latent heat is the most promising way to achieve efficient solar energy harvesting and rapid thermal energy storage. However, exfoliating high-quality black phosphorene nanosheets  remains challenging, Furthermore, an efficient strategy that can construct the aligned black phosphorene frameworks to maximize thermal conductivity enhancement is still lacking. Herein, high-quality black phosphorene nanosheets are prepared by an optimized exfoliating strategy. Meanwhile, by regulating the temperature gradient during freeze-casting, the framework consisting of shipshape aligned black phosphorene at long-range is successfully fabricated, improving the thermal conductivity of the poly(ethylene glycol) matrix up to 1.81 W m-1  K-1 at 20 vol% black phosphorene loading. The framework also endows the composite with excellent phase-change material encapsulation capacity and  high latent heat of 103.91 J g-1 . It is envisioned that the work advances the paradigm of contrasting frameworks with nanosheets toward controllable structure thermal enhancement of the composites.

4.
Fish Shellfish Immunol ; 124: 324-331, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35429625

RESUMEN

To explore the immune function of C-type lectin in shrimp, one recombinant C-type lectin (LvLec) was injected into Litopenaeus vannamei. There were four treatments in the experiment: saline group (as control group), recombinant C-type lectin group (LvLec, 1 mg mL-1), Vibrio harveyi group (V. harveyi, 106 cfu mL-1) and recombinant C-type lectin combined with Vibrio harveyi group (LvLec + V. harveyi, 1 mg mL-1 + 106 cfu mL-1). The sampling time was set at 0, 3, 6, 9, 12, 24 h after the injection. The results showed that the total hemocyte count decreased significantly and the phagocytic activity improved notably after the injection of LvLec, V. harveyi or LvLec + V. harveyi. Prophenoloxidase (proPO) activity decreased, while phenoloxidase (PO) activity increased and the changing degree of each group exhibited a significant difference. The hemagglutinating activity and bacteriolytic activity improved significantly, while the antimicrobial activity did not show a remarkable change in all of the groups. There were also changes that occurred in the levels of second messengers (cAMP, cGMP) and protein kinase (PKA, PKG). After the injection of LvLec, V. harveyi or LvLec + V. harveyi, the concentration of cGMP and PKA increased significantly, while the concentration of cAMP and PKG did not change remarkably. The results above suggested that rLvLec could induce nonspecific immune response, including phagocytosis, release of PO, hemagglutination and bacteriolysis through cGMP-PKA pathway in vivo.


Asunto(s)
Hemocitos , Penaeidae , Animales , Inmunidad Innata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Vibrio
5.
Infection ; 48(3): 445-452, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32301099

RESUMEN

AIMS AND BACKGROUND: The COVID-19 outbreak spread in China and is a threat to the world. We reported on the epidemiological, clinical, laboratory, and radiological characteristics of children cases to help health workers better understand and provide timely diagnosis and treatment. METHODS: Retrospectively, two research centers' case series of 67 consecutive hospitalized cases including 53 adult and 14 children cases with COVID-19 between 23 Jan 2020 and 15 Feb 2020 from Jinan and Rizhao were enrolled in this study. Epidemiological, clinical, laboratory, and radiological characteristics of children and adults were analyzed and compared. RESULTS: Most cases in children were mild (21.4%) and conventional cases (78.6%), with mild clinical signs and symptoms, and all cases were of family clusters. Fever (35.7%) and dry cough (21.4%) were described as clinical manifestations in children cases. Dry cough and phlegm were not the most common symptoms in children compared with adults (p = 0.03). In the early stages of the disease, lymphocyte counts did not significantly decline but neutrophils count did in children compared with adults (p = 0.02). There was a lower level of CRP (p = 0.00) in children compared with adults. There were 8 (57.1%) asymptomatic cases and 6 (42.9%) symptomatic cases among the 14 children cases. The age of asymptomatic patients was younger than that of symptomatic patients (p = 0.03). Even among asymptomatic patients, 5 (62.5%) cases had lung injuries including 3 (60%) cases with bilateral involvement, which was not different compared with that of symptomatic cases (p = 0.58, p = 0.74). CONCLUSIONS: The clinical symptoms of children are mild, there is substantial lung injury even among children, but that there is less clinical disease, perhaps because of a less pronounced inflammatory response, and that the occurrence of this pattern appears to inversely correlate with age.


Asunto(s)
Betacoronavirus/patogenicidad , Infecciones por Coronavirus/patología , Tos/patología , Fiebre/patología , Pulmón/virología , Neumonía Viral/patología , Adulto , Factores de Edad , Enfermedades Asintomáticas , Proteína C-Reactiva/inmunología , Proteína C-Reactiva/metabolismo , COVID-19 , Niño , China/epidemiología , Infecciones por Coronavirus/diagnóstico por imagen , Infecciones por Coronavirus/epidemiología , Tos/diagnóstico por imagen , Tos/epidemiología , Citocinas/inmunología , Citocinas/metabolismo , Fiebre/diagnóstico por imagen , Fiebre/epidemiología , Humanos , Pulmón/diagnóstico por imagen , Pulmón/inmunología , Pulmón/patología , Linfocitos/inmunología , Linfocitos/virología , Neutrófilos/inmunología , Neutrófilos/virología , Pandemias , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/epidemiología , Estudios Retrospectivos , SARS-CoV-2 , Tomografía Computarizada por Rayos X
6.
Fish Shellfish Immunol ; 89: 35-42, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30890430

RESUMEN

C-type lectin has received widespread attention in animal immunomodulation functions since it was discovered, but it is still limited in crustaceans. The present study is to explore effects of one recombinant C-type lectin (LvLec protein) on haemocyte immune response in Litopenaeus vannamei (L. vannamei). The methods of keeping haemocyte immune activity were optimised by the Key Laboratory of Mariculture. The experiment was divided into four groups: control group, recombinant protein group (LvLec protein, 1.0 mg mL-1), Lipopolysaccharide group (LPS, 1.0 mg mL-1), and LPS combine with LvLec protein group (LPS + LvLec protein, 1.0 mg mL-1 + 1.0 mg mL-1), while each group processes 0, 3, 6, 9, 12, and 24 h respectively. The results showed that the haemocyte count reduced, while the exocytosis PO activity, hemagglutinating activity and phagocytic activity promoted, and the concentration of cGMP and PKA increased after LvLec protein treatment. However, the levels of antibacterial activity and bacteriolytic activity as well as the concentrations of cAMP and PKG did not change significantly after treating with LvLec protein, LPS or LPS + LvLec protein. Therefore, these results suggest that LvLec protein can stimulate the exocytosis PO activity through cGMP-PKA pathway to affect the phagocytic activity and hemagglutinating activity of L. vannamei haemocytes in vitro.


Asunto(s)
Hemocitos/inmunología , Inmunidad Innata/genética , Lectinas Tipo C/genética , Lectinas Tipo C/inmunología , Penaeidae/genética , Penaeidae/inmunología , Animales , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Catecol Oxidasa/genética , Catecol Oxidasa/metabolismo , Precursores Enzimáticos/genética , Precursores Enzimáticos/metabolismo , Hemocitos/enzimología , Inmunomodulación/genética , Lipopolisacáridos/fisiología , Penaeidae/enzimología , Fagocitosis/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología
7.
Mikrochim Acta ; 186(7): 413, 2019 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-31187252

RESUMEN

The authors of "A glassy carbon electrode modified with N-doped carbon dots for improved detection of hydrogen peroxide and paracetamol (Microchimica Acta 185, no. 2 (2018): 87)" wish to replace the incorrect images of Fig. 1C, 1D shown below.

8.
Nano Lett ; 18(7): 4611-4617, 2018 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-29911386

RESUMEN

Nanostructures in silicon (Si) induced by phase transformations have been investigated during the past 50 years. Performances of nanostructures are improved compared to that of bulk counterparts. Nevertheless, the confinement and loading conditions are insufficient to machine and fabricate high-performance devices. As a consequence, nanostructures fabricated by nanoscale deformation at loading speeds of m/s have not been demonstrated yet. In this study, grinding or scratching at a speed of 40.2 m/s was performed on a custom-made setup by an especially designed diamond tip (calculated stress under the diamond tip in the order of 5.11 GPa). This leads to a novel approach for the fabrication of nanostructures by nanoscale deformation at loading speeds of m/s. A new deformation-induced nanostructure was observed by transmission electron microscopy (TEM), consisting of an amorphous phase, a new tetragonal phase, slip bands, twinning superlattices, and a single crystal. The formation mechanism of the new phase was elucidated by ab initio simulations at shear stress of about 2.16 GPa. This approach opens a new route for the fabrication of nanostructures by nanoscale deformation at speeds of m/s. Our findings provide new insights for potential applications in transistors, integrated circuits, diodes, solar cells, and energy storage systems.

9.
Mikrochim Acta ; 185(2): 87, 2018 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-29594682

RESUMEN

Nitrogen doped carbon dots (NCDs) were synthesized using a low temperature approach and used to modify a glassy carbon electrode (GCE) via dipping. The oxygen groups on the surface of the NCDs, and the charge delocalization of the NCDs warrant an excellent electrocatalytic activity of the GCE toward oxidation of paracetamol (PA) and reduction of H2O2. PA and H2O2 were detected at 0.34 V and -0.4 V (both vs. Ag/AgCl) using differential pulse voltammetry and amperometric I-T measurement, respectively. The modified GCE has a linear response to PA in the 0.5 to 600 µM concentration range, and to H2O2 in the 0.05 µM to 2.25 mM concentration range. The detection limits are 157 nM and 41 nM, respectively. In our perception, the modified GCE holds promise for stable, selective and sensitive determination of PA and H2O2 in pharmaceutical analysis. Graphic abstract Nitrogen doped carbon dots (NCDs) were synthesized and used to modify a glassy carbon electrode. Surface functional groups on NCDs can trigger electrocatalytic reactions toward paracetamol oxidation and H2O2 reduction with high sensitivities.

10.
BMC Infect Dis ; 14: 368, 2014 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-24993389

RESUMEN

BACKGROUND: The impact of pregnancy on the clinical course of acute hepatitis B (AHB) is still largely unclear, mainly because most studies have not included matched controls. This study was conducted to investigate the clinical features and outcome of AHB in pregnancy using matched controls. METHODS: Consecutive AHB inpatients who were admitted to Jinan Infectious Disease Hospital, Jinan, between January 2006 and December 2010 were evaluated and followed. Demographic data, clinical manifestations, and results of laboratory tests were compared between pregnant patients and age and sex matched non-pregnant patients at admission, discharge, and final follow-up. RESULTS: A total of 618 AHB inpatients were identified during the study period. 22 pregnant patients and 87 age and sex matched non-pregnant patients were enrolled in this study. Prodromal fever was less common (0% vs. 20.7%, P=0.02), serum alanine aminotransferase levels were significantly lower, and HBsAg>250 IU/mL rate and serum bilirubin levels were significantly higher in pregnant patients than in non-pregnant patients. After a mean (range) of 7(5.2-8.3) months follow-up, 18.2% pregnant patients and 4.6% non-pregnant patients were still HBsAg positive (P=0.03). For pregnant patients, the relative risk (95% confidence interval) of HBsAg positive at the end of follow-up was 4.6 (1.1-20.2). The median (95% confidence interval) days of HBsAg seroclearance form disease onset in pregnant and non-pregnant patients were 145.0 (110.5-179.5) and 80.0 (62.6-97.4), respectively. CONCLUSIONS: The HBsAg loss and seroconversion were delayed and lower in pregnant patients. Pregnancy might be a possible risk of chronicity following acute HBV infection.


Asunto(s)
Hepatitis B/sangre , Hepatitis B/inmunología , Complicaciones Infecciosas del Embarazo/virología , Adulto , Estudios de Casos y Controles , ADN Viral/sangre , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Embarazo , Complicaciones Infecciosas del Embarazo/sangre , Complicaciones Infecciosas del Embarazo/inmunología , Adulto Joven
11.
Diagn Microbiol Infect Dis ; 109(2): 116264, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38493510

RESUMEN

This study was performed to investigate the frequency of angiogenic T cells (CD4+ Tang cells) among CD4+ T cells in patients with hepatitis B-induced liver cirrhosis (HBV-LC) and to evaluate the predictive role of these cells in the clinical outcome. In total, 185 patients with HBV-LC were recruited to measure the frequency of CD4+ Tang cells and chemokine levels using flow cytometry. RESULTS: There was 11.4% of death after 3-momth follow-up. The AUC for the ability of the frequency of CD4+ Tang cell to predict death was 0.724 (higher than those for the MELD score, FIB-4 score, and Child-Pugh classification). Cox regression analysis revealed an association between the frequency of CD4+ Tang cells and a 3-month survival chance. CONCLUSIONS: The lower frequency of CD4+ T ang cells was correlated with the severity of HBV-LC and may serve as a prognostic predictor.


Asunto(s)
Linfocitos T CD4-Positivos , Cirrosis Hepática , Humanos , Masculino , Femenino , Cirrosis Hepática/virología , Pronóstico , Persona de Mediana Edad , Linfocitos T CD4-Positivos/inmunología , Adulto , Hepatitis B/complicaciones , Citometría de Flujo , Quimiocinas/sangre , Hepatitis B Crónica/complicaciones , Anciano
12.
Immun Inflamm Dis ; 12(9): e70002, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39222064

RESUMEN

OBJECTIVE: Hepatocellular carcinoma (HCC) poses a significant challenge to global health. Its pathophysiology involves interconnected processes, including cell proliferation, autophagy, and macrophage polarization. However, the role of Absent in Melanoma 2 (AIM2) in HCC remains elusive. METHODS: The expression of AIM2 in Huh-7 and Hep3B cell lines was manipulated and cell proliferation, autophagy, apoptosis, and migration/invasion, together with the polarization of M2 macrophages, were evaluated. The markers of autophagy pathway, LC3B, Beclin-1, and P62, underwent examination through Western blot analysis. An autophagy inhibitor, 3-MA, was used to measured the role of autophagy in HCC. Finally, the effect of AIM2 overexpression on HCC was further evaluated using a subcutaneous tumor model in nude mice. RESULTS: Our results established that AIM2 overexpression inhibits HCC cell proliferation, migration, and invasion while promoting apoptosis and autophagy. Conversely, knockdown of AIM2 engendered opposite effects. AIM2 overexpression was correlated with reduced M2 macrophage polarization. The autophagy inhibitor substantiated AIM2's role in autophagy and identified its downstream impact on cell proliferation, migration, invasion, and macrophage polarization. In the in vivo model, overexpression of AIM2 led to the inhibition of HCC tumor growth. CONCLUSION: The findings underscore AIM2's crucial function in modulating major biological processes in HCC, pointing to its potential as a therapeutic target. This study inaugurally demonstrated that AIM2 activates autophagy and influences macrophage polarization, playing a role in liver cancer progression.


Asunto(s)
Autofagia , Carcinoma Hepatocelular , Movimiento Celular , Proliferación Celular , Neoplasias Hepáticas , Macrófagos , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Autofagia/genética , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Animales , Humanos , Ratones , Macrófagos/metabolismo , Macrófagos/inmunología , Línea Celular Tumoral , Movimiento Celular/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Apoptosis/genética , Ratones Desnudos , Ensayos Antitumor por Modelo de Xenoinjerto , Activación de Macrófagos/genética
13.
Adv Mater ; 36(37): e2311335, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38847403

RESUMEN

The challenges associated with heat dissipation in high-power electronic devices used in communication, new energy, and aerospace equipment have spurred an urgent need for high-performance thermal interface materials (TIMs) to establish efficient heat transfer pathways from the heater (chip) to heat sinks. Recently, emerging 2D materials, such as graphene and boron nitride, renowned for their ultrahigh basal-plane thermal conductivity and the capacity to facilitate cross-scale, multi-morphic structural design, have found widespread use as thermal fillers in the production of high-performance TIMs. To deepen the understanding of 2D material-based TIMs, this review focuses primarily on graphene and boron nitride-based TIMs, exploring their structures, properties, and applications. Building on this foundation, the developmental history of these TIMs is emphasized and a detailed analysis of critical challenges and potential solutions is provided. Additionally, the preparation and application of some other novel 2D materials-based TIMs are briefly introduced, aiming to offer constructive guidance for the future development of high-performance TIMs.

14.
Plant Physiol Biochem ; 206: 107850, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38042099

RESUMEN

Understanding the physiological mechanism underlying nitrogen levels response to a low red/far-red ratio (R/FR) can provide new insights for optimizing wheat yield potential but has been not well documented. This study focused on the changes in nitrogen levels, nitrogen assimilation and nitrate uptake in wheat plants grown with and without additional far-red light. A low R/FR reduced wheat nitrogen accumulation and grain yield compared with the control. The levels of total nitrogen, free amino acid and ammonium were decreased in leaves but nitrate content was temporarily increased under a low R/FR. The nitrate reductase (NR) activity in leaves was more sensitive to a low R/FR than glutamine synthetase, glutamate synthase, glutamic oxalacetic transaminase and glutamic-pyruvic transaminase. Further analysis showed that a low R/FR had little effect on the NR activation state but reduced the level of NR protein and the expression of encoding gene TaNR1.2. Interestingly, a low R/FR rapidly induced TaPIL5 expression rather than TaHY5 and other members of TaPILs in wheat, suggesting that TaPIL5 was the key transcription factor response to a low R/FR in wheat and might be involved in the downregulation of TaNR1.2 expression. Besides, a low R/FR downregulated the expression of TaNR1.2 in leaves earlier than that of TaNRT1.1/1.2/1.5/1.8 in roots, which highlights the importance of NR and nitrogen assimilation in response to a low R/FR. Our results provide revelatory evidence that restricted nitrate reductase associated with downregulated TaNR1.2 and upregulated TaPIL5 mediate the suppression of nitrogen assimilation under a low R/FR in wheat.


Asunto(s)
Compuestos de Amonio , Triticum , Nitrato-Reductasa/genética , Nitrato-Reductasa/metabolismo , Triticum/metabolismo , Nitratos/metabolismo , Nitrógeno/metabolismo , Compuestos de Amonio/metabolismo
15.
ACS Omega ; 9(25): 26973-26982, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38947776

RESUMEN

With the development of high-rise and large-scale modern structures, traditional concrete has become a design limitation due to its excessive dead weight. High-strength lightweight concrete is being emphasized. Lightweight concrete has low density and the characteristics of a brittle material. This is an important factor affecting the strength and ductility of the lightweight concrete. To improve these shortcomings and proffer solutions, a three-phase composite lightweight concrete was prepared using a combination of tumbling and molding methods. This paper investigates the various influencing factors such as the stacking volume fraction of GFR-EMS, the type of fiber, and the content and length of fiber in the matrix. Studies have shown that the addition of fibers significantly increases the compressive strength of the concrete. The compressive strength of concrete with a 12 mm basalt fiber (BF) (1.5%) admixture is 9.08 MPa, which is 62.43% higher than that of concrete without the fiber admixture. The compressive strength was increased by 27.53 and 21.88% compared to concrete containing 3 mm BF (1.5%) and 0.5% BF (12 mm), respectively. Fibers can fill the pore defects within the matrix. Mutually overlapping fibers easily form a network structure to improve the bond between the cement matrix and the aggregate particles. The compressive strength of lightweight concrete with the addition of BF was 16.71% higher than that with the addition of polypropylene fiber (PPF) with the same length and content of fibers. BF has been shown to be more effective in improving the mechanical properties of concrete. In this work, the compressive mechanism and optimum preparation parameters of a three-phase composite lightweight concrete were analyzed through compression tests. This provides some insights into the development of lightweight concrete.

16.
Mater Horiz ; 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39311412

RESUMEN

Dielectric capacitors are pivotal elements in advanced pulsed power devices and high-voltage, high-capacity power electronic converters, crucial for efficient energy storage. However, a major challenge remains the significant reduction in energy density and charge-discharged efficiency of dielectric polymers under high temperatures, primarily due to heightened electrical conduction losses. This study introduces a universal approach of heterojunction interface engineering in polyethersulfone (PESU) composites, aimed at improving capacitive performance across a broad temperature range. The introduction of one-dimensional heterojunction BaTiO3@Al2O3 nanofibers with large aspect ratios could enhance both the dielectric constant (εr) and breakdown strength (Eb). Specifically, the creation of hierarchical interfaces increases the trap density and energy levels for mobile charges, effectively reducing conduction losses and improving Eb under high-temperature conditions. Consequently, the PESU-3 vol% BaTiO3@Al2O3 nanocomposite achieves an excellent energy density of 7.3 J cm-3 with over 90% retention at 150 °C and 550 MV m-1. Finite element simulations further confirm that the heterojunction structure of BaTiO3@Al2O3 nanofibers effectively inhibits the growth of breakdown paths. This work demonstrates that hierarchical interface engineering offers a powerful strategy to enhance capacitive performance in dielectric polymer composites under harsh conditions.

17.
ACS Appl Mater Interfaces ; 16(6): 7732-7741, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38306189

RESUMEN

The implementation of passive cooling strategies is crucial for transitioning from the current high-power- and energy-intensive thermal management practices to more environmentally friendly and carbon-neutral alternatives. Among the various approaches, developing thermal management materials with high thermal conductivity and emissivity for effective cooling of personal and wearable devices in both indoor and outdoor settings poses significant challenges. In this study, we successfully fabricated a cooling patch by combining biodegradable silk fibroin with boron nitride nanosheets. This patch exhibits consistent heat dissipation capabilities under different ambient conditions. Leveraging its excellent radiative cooling efficiency (Rsolar = 0.89 and εLWIR = 0.84) and high thermal conductivity (in-plane 27.58 W m-1 K-1 and out-plane 1.77 W m-1 K-1), the cooling patch achieves significant simulated skin temperature reductions of approximately 2.5 and 8.2 °C in outdoor and indoor conditions, respectively. Furthermore, the film demonstrates excellent biosafety and can be recycled and reused for at least three months. This innovative BNNS/SF film holds great potential for advancing the field of personal thermal management materials.

18.
Biomater Sci ; 12(5): 1281-1293, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38252410

RESUMEN

Acute liver injury (ALI) is a highly fatal condition characterized by sudden massive necrosis of liver cells, inflammation, and impaired coagulation function. Currently, the primary clinical approach for managing ALI involves symptom management based on the underlying causes. The association between excessive reactive oxygen species originating from macrophages and acute liver injury is noteworthy. Therefore, we designed a novel nanoscale phase variant contrast agent, denoted as PFP@CeO2@Lips, which effectively scavenges reactive oxygen species, and enables visualization through low intensity pulsed ultrasound activation. The efficacy of the nanoparticles in scavenging excess reactive oxygen species from RAW264.7 and protective AML12 cells has been demonstrated through in vitro and in vivo experiments. Additionally, these nanoparticles have shown a protective effect against LPS/D-GalN attack in C57BL/6J mice. Furthermore, when exposed to LIPUS irritation, the nanoparticles undergo liquid-gas phase transition and enable ultrasound imaging.


Asunto(s)
Hígado , Nanopartículas , Ratones , Animales , Especies Reactivas de Oxígeno , Ratones Endogámicos C57BL , Hígado/diagnóstico por imagen , Inflamación , Ondas Ultrasónicas
19.
Mater Horiz ; 11(17): 4064-4074, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39042375

RESUMEN

In the pursuit of effective thermal management for electronic devices, it is crucial to develop insulation thermal interface materials (TIMs) that exhibit exceptional through-plane thermal conductivity, low thermal resistance, and minimal compression modulus. Boron nitride (BN), given its outstanding thermal conduction and insulation properties, has garnered significant attention as a potential material for this purpose. However, previously reported BN-based composites have consistently demonstrated through-plane thermal conductivity below 10 W m-1 K-1 and high compression modulus, whilst also presenting challenges in terms of mass production. In this study, low molecular weight polydimethylsiloxane (PDMS) and large-size BN were utilized as the foundational materials. Utilizing a rolling-curing integrated apparatus, we successfully accomplished the continuous preparation of large-sized, high-adhesion BN films. Subsequent implementation of stacking, cold pressing, and vertical cutting techniques enabled the attainment of a remarkable BN-based TIM, characterized by an unprecedented through-plane thermal conductivity of up to 12.11 W m-1 K-1, remarkably low compression modulus (55 kPa), and total effective thermal resistance (0.16 °C in2 W-1, 50 Psi). During the TIMs performance evaluation, our TIMs demonstrated superior heat dissipation capabilities compared with commercial TIMs. At a heating power density of 40 W cm-2, the steady-state temperature of the ceramic heating element was found to be 7 °C lower than that of the commercial TIMs. This pioneering feat not only contributes valuable technical insights for the development of high-performance insulating TIMs but also establishes a solid foundation for widespread implementation in thermal management applications across a range of electronic devices.

20.
ACS Appl Mater Interfaces ; 16(31): 41435-41449, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39069834

RESUMEN

Smart responsive materials are capable of responding to external stimuli and, compared to traditional materials, can be effectively reused and reduce usage costs in applications. However, smart responsive materials often face challenges such as the inability to repair extensive damage, instability in long-term performance, and inapplicability in extreme environments. This study combines 2D diamond nanosheets with organic fluorinated molecules to prepare a smart nanofluid (fluorinated diamond nanosheets, F-DN) with self-healing and self-adhesion properties. This smart nanofluid can be used to design various coatings for different applications. For example, coatings prepared on textured steel plates using the drop-casting method have excellent superhydrophobic and high oleophobic properties; coatings on titanium alloy plates achieve low friction and wear in the presence of lubricating additives of F-DN in perfluoropolyether (PFPE). Most impressively, coatings on steel plates not only provide effective corrosion resistance but also have the ability to self-heal significant damage (approximately 2 mm in width), withstand extremely low temperatures (-64 °C), and resist long-term corrosion factors (immersion in 3.5 wt % NaCl solution for 35 days). Additionally, it can act as a "coating glue" to repair extensive damage to other corrosion-resistant organic coatings and recover their original protective properties. Therefore, the smart nanofluid developed in this study offers diverse applications and presents new materials system for the future development of smart responsive materials.

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